Macroecology is the subfield of ecology which deals with the study of relationships between organisms and their environment at large spatial scales to characterise and explain statistical patterns of abundance, distribution and diversity. The term was coined by James Brown of the University of New Mexico and Brian Maurer of Michigan State University in a 1989 paper in Science.
Macroecology approaches the idea of studying ecosystems using a "top down" approach. It seeks understanding through the study of the properties of the system as a whole; Kevin Gaston and Tim Blackburn make the analogy to seeing the forest for the trees (literally).
Classic ecological questions amenable to study through the techniques of macroecology include questions of species richness and the species-area curve , range size , body size and species abundance . For example, the relationship between abundance and range size (why species that maintain large local population sizes tend to be widely distributed, while species that are less abundant tend to have restricted ranges) has received much attention.
Brown, J.H and B.A. Maurer. 1989. Macroecology: The division of food ad space among species on continents. Science 243: 1145-1150
Brown, J.H. 2000. Macroecology. University of Chicago Press. ISBN 0-226-07614-8
Gaston, K.J. and T.M. Blackburn. 2000. Pattern and Process in Macroecology. Blackwell Science. ISBN 0-632-05653-3